flex中httpservice与java后台交互的两种传值方式

环境：myeclipse8.5+flex4+blazeds
            描述：flex4中httpservice与服务器端交互的值传递问题
            方式一：通过<s:request/>标签进行交互，在该标签内部以要传递的参数名作为该标签内的子标签，值作为内容进行传递，服务端接受数据采用request.getParmeter("参数名")获取数据.
            示例代码：
            flex中的代码：

<!-- 定义HttpService发送请求 -->
         < s:HTTPService  id ="service"  
                       url ="http://localhost:8080/testhttpservice/testHttpServiceServlet"  
                       useProxy ="false"  
                       fault ="service_faultHandler(event)"  
                       result ="service_resultHandler(event)" >
             <!-- 第一种传值方式 -->
            
             < s:request  >
                 <!-- 参数名称作标签,中间填充参数值 -->
                 < username > {txtusername.text} </ username >
                 < password > {txtpassword.text} </ password >
             </ s:request >
            
         </ s:HTTPService >

        后台接受参数的代码：

         // 获取flex传递的参数 username password
        String username = request.getParameter( " username " );
         // get方式处理乱码
         // username=new String(username.getBytes("ISO-8859-1"),"utf-8");
        String password = request.getParameter( " password " );
         // password=new String(password.getBytes("ISO-8859-1"),"utf-8");

        方式二：第二种传值方式通过send()方法传值send方法中传递参数 ，服务端接受数据采用request.getParmeter("参数名")获取数据.
        示例代码：

                 //第二种传值方式 通过send()方法传值 send方法中传递参数 
                //定义一object对象
                var val:Object=new Object();
                //分别将文本框username，password的值传递到后台
                //object对象.参数名=值   传值操作
                val.username=txtusername.text;
                val.password=txtpassword.text;
                service.send(val);

        贴出完整的代码：
        服务器端:

package  com.servlet;

import  java.io.IOException;
import  java.io.PrintWriter;
import  java.util.ArrayList;
import  java.util.List;

import  javax.servlet.ServletException;
import  javax.servlet.http.HttpServlet;
import  javax.servlet.http.HttpServletRequest;
import  javax.servlet.http.HttpServletResponse;

/**
 * 功能描述:flex httpservice与java交互参数传递探讨<br>
 * @author sxyx2008<br>
 * @date 2010-07-19
 *
 */
@SuppressWarnings( " serial " )
public   class  TestHttpServiceServlet  extends  HttpServlet  {
    
    @Override
    protected void service(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        //处理post方式乱码
        request.setCharacterEncoding("utf-8");
        //设置浏览器输出字符编码
        response.setCharacterEncoding("utf-8");
        PrintWriter writer=response.getWriter();
        //获取flex传递的参数 username password
        String username=request.getParameter("username");
        //get方式处理乱码
        
        //username=new String(username.getBytes("ISO-8859-1"),"utf-8");
        String password=request.getParameter("password");
        //password=new String(password.getBytes("ISO-8859-1"),"utf-8");
        
        //构建一个list存放一些数据用来模拟用户是否存在这一功能
        List<String> list=new ArrayList<String>();
        list.add("张三");
        list.add("李四");
        list.add("王五");
        list.add("曹操");
        list.add("孙权");
        list.add("刘备");
        //检验用户
        if(list.contains(username)){
            writer.print("存在:"+username+"客户端传递的密码是:"+password);
        }else{
            writer.print("找不到:"+username+"客户端传递的密码是:"+password);
        }
        
    }
}

        flex代码：

<? xml version="1.0" encoding="utf-8" ?>
< s:Application  xmlns:fx ="http://ns.adobe.com/mxml/2009"  
               xmlns:s ="library://ns.adobe.com/flex/spark"  
               xmlns:mx ="library://ns.adobe.com/flex/mx"  minWidth ="955"  minHeight ="600" >
     < fx:Script >
         <![CDATA[
            import mx.controls.Alert;
            import mx.rpc.events.FaultEvent;
            import mx.rpc.events.ResultEvent;

            //调用失败
            protected function service_faultHandler(event:FaultEvent):void
            {
                Alert.show("失败了:"+event.message,"提示");
            }

            //调用成功
            protected function service_resultHandler(event:ResultEvent):void
            {
                Alert.show("成功了:"+event.result as String,"提示");
            }
    
            //调用
            protected function button1_clickHandler(event:MouseEvent):void
            {
                //第一种传值方式                
                //service.send();
                
                //第二种传值方式 通过send()方法传值 send方法中传递参数 
                //定义一object对象
                var val:Object=new Object();
                //分别将文本框username，password的值传递到后台
                //object对象.参数名=值   传值操作
                val.username=txtusername.text;
                val.password=txtpassword.text;
                service.send(val);
            }

         ]]>
     </ fx:Script >
     < fx:Declarations >
         <!--  将非可视元素（例如服务、值对象）放在此处  -->
         <!-- 定义HttpService发送请求 -->
         < s:HTTPService  id ="service"  
                       url ="http://localhost:8080/testhttpservice/testHttpServiceServlet"  
                       useProxy ="false"  
                       fault ="service_faultHandler(event)"  
                       result ="service_resultHandler(event)" >
             <!-- 第一种传值方式 -->
            
             < s:request  >
                 <!-- 参数名称作标签,中间填充参数值 -->
                 < username > {txtusername.text} </ username >
                 < password > {txtpassword.text} </ password >
             </ s:request >
            
         </ s:HTTPService >
        
        
     </ fx:Declarations >
     < s:TextInput  x ="332"  y ="196"  id ="txtusername" />
     < s:TextInput  x ="332"  y ="256"  id ="txtpassword"  displayAsPassword ="true" />
     < s:Button  x ="357"  y ="311"  label ="发送"  click ="button1_clickHandler(event)" />
     < s:Label  x ="290"  y ="206"  text ="用户名:" />
     < s:Label  x ="297"  y ="266"  text ="密码:" />
</ s:Application >